Flexible and/or pushable tubular device

ABSTRACT

The teachings herein relate to devices for insertion into a cavity, opening or other passageway that requires the bending of the device to conform to a curved or even tortuous shape of the path. The devices include axial support components for translating forces for moving the device forward in the path. The axial support components preferably include adjacent components capable of rocking for tilting the device in one or more directions. The device preferably includes one or more lateral support components for limiting any lateral motion of an axial support component relative to an adjacent axial support component.

FIELD

The teachings herein are directed at methods and devices including aflexible tube, such as medical devices for inserting through a curved ortortuous path. For example, the teachings herein may be employed in acatheter, stent or an access sheath.

BACKGROUND

Examples of medical devices for inserting into a curved path aredescribed in U.S. Pat. No. 8,721,826 B2, and PCT Patent ApplicationsWO2014074986 A1 and WO2010105649 A1, all incorporated herein byreference. In general, these devices employ a tubular material thatflexes back and forth. To enhance the flexing, the tubular structure mayhave slits or openings that reduce the resistance to the bending motion.However, at the bend points or bend regions, the tube is a contiguousmaterial, directly connected and the ability to bend the tubularmaterial requires that it be formed of a generally flexible material.

There is a need for tubular members which can be turned on one or moredirections to fit through a curved or tortuous path. There is a need fortubular members having adjacent components that are easily rockedagainst each other. There is also a need for tubular members that areporous. There is also a need for tubular members that are kink freeand/or kink resistant. There is also a need for tubular members that caneasily move in an axial direction in response to an axial force (e.g.,for moving in and out of a curved or tortuous path).

SUMMARY

In one aspect, the teachings herein are directed at a medical devicecomprising: a tubular member having a proximal end, a distal end, anouter surface, an inner surface, a longitudinal direction (i.e., anaxial direction) along a length of the tubular member, a passageextending from the proximal end to the distal end in the longitudinaldirection, and a cross-section perpendicular to the longitudinaldirection. The tubular member includes a plurality of axial supportcomponents in a stacked arrangement including at least a first axialsupport component and a second adjacent axial support component locatedabove the first axial support component in the proximal direction,wherein each of the first and second axial support components has a topedge surface facing the proximal end and a bottom edge surface facingthe distal end, wherein a first portion of the top edge surface of thefirst axial support component contacts a first portion of the bottomedge surface of the second axial support component (e.g., so that anaxial force is translated between the adjacent axial supportcomponents), and a second portion of the top edge surface of the firstaxial support component is spaced apart from the bottom edge surface ofthe second axial support component (e.g., so that the axial directioncan bend between adjacent axial support components), wherein the firstand second portions of the top edge surface are at different locationsalong the circumference of the first axial component. The tubular memberalso includes one or more lateral support components in contact with theaxial support components for reducing lateral movement of adjacent axialsupport components relative to each other.

In another aspect, the teachings herein are directed at the manufactureof a device including a plurality of axial support components and one ormore lateral support components.

In another aspect, the teachings herein are directed at a methodcomprising inserting a device into a cavity or other opening andsteering an end of the device through the opening.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of an illustrative tubular member having aninternal passage in a generally linear configuration.

FIG. 2 is a perspective view of an illustrative tubular member having aninternal passage and having a non-linear (e.g., curved) configuration.

FIG. 3 is a perspective view of an illustrative tubular member in atortuous passage.

FIG. 4 is a front view of an illustrative tubular member including aplurality of axial support members (e.g., in a stacked arrangement) andhaving an internal passage with one or more components extending throughthe internal passage.

FIG. 5 is a perspective view illustrating features that may be found ina tubular member.

FIG. 6 is a front view of FIG. 5.

FIG. 7 is a right side view of FIG. 5.

FIG. 8 is a rear view of a portion of FIG. 5.

FIG. 9 is a perspective view sectioned by a plane going through the axisof the passage, showing features of the tubular member of FIG. 5.

FIG. 10 is a left side view sectioned by a plane through the axis of thepassage showing features of the tubular member of FIG. 5.

FIG. 11 is a top view showing features of the tubular member of FIG. 10.

FIG. 12 is a top view of an illustrative tubular member according to theteachings herein.

FIG. 13 is a perspective view of components that having top and bottomedges that mate with one another.

FIG. 14 is an illustrative drawing showing the components of FIG. 13stacked in an axial direction.

FIG. 15 is an illustrative drawing showing the components of FIG. 13stacked with each component angled relative to an adjacent component.

FIG. 16A is a perspective view showing features of an illustrative axialsupport component having a generally helical structure.

FIG. 16B is a front view showing the arrangement of the axial supportcomponents of FIG. 16A.

FIG. 16C is a left side view of FIG. 16A.

FIG. 17A is a sectional view of FIG. 16B.

FIG. 17B is a sectional view of FIG. 16C.

FIG. 18 is a top view of FIG. 16A, showing the passageway through thestructure.

FIG. 19 is a representative side view of FIG. 16A showing the helicalstructure.

FIG. 20, FIG. 21, and FIG. 22 are views of an illustrative axial supportcomponent as represented by a single turn of the helical structure ofFIG. 16A. FIG. 20 shows the top view, FIG. 21 shows the front view, andFIG. 22 shows the left side view.

FIG. 23A is a drawing of a front view of an illustrative arrangement ofaxial support components.

FIG. 23B is a drawing of a front view of an illustrative first axialsupport component of FIG. 23A.

FIG. 23C is a drawing of a front view of an illustrative second axialsupport component of FIG. 23A having a different shape as the firstaxial support component or arranged at an angle of rotation (e.g., about180°) relative to the first axial support component.

FIG. 24A is a drawing of a front view of an illustrative arrangement ofaxial support components.

FIG. 24B is a drawing of a front view of an illustrative first axialsupport component of FIG. 24A.

FIG. 24C is a drawing of a front view of an illustrative second axialsupport component of FIG. 24A having a different shape as the firstaxial support component or arranged at an angle of rotation (e.g., about180°) relative to the first axial support component.

FIG. 25A is a drawing of a front view of an illustrative arrangement ofaxial support components.

FIG. 25B is a drawing of a front view of an illustrative first axialsupport component of FIG. 25A.

FIG. 25C is a drawing of a front view of an illustrative second axialsupport component of FIG. 25A having a different shape as the firstaxial support component or arranged at an angle of rotation (e.g., about180°) relative to the first axial support component.

FIG. 25D is a drawing of a front view of an illustrative third axialsupport component of FIG. 25A having a different shape as the first andsecond axial support component and/or arranged at an angle of rotation(e.g., about +/−90°) relative to the first axial support component.

FIG. 25E is a drawing of a front view of an illustrative fourth axialsupport component of FIG. 25A having a different shape as the first,second, and third axial support components or arranged at an angle ofrotation (e.g., about 180°) relative to the third axial supportcomponent.

FIG. 26 is a drawing of a front view of a tubular member showing stackedaxial support components having adjacent axial support componentsconnected by a corrugated region.

FIG. 27 is a drawing of an illustrative precursor part for preparing thestructure of FIG. 26. In the precursor part, the adjacent axial supportcomponents may be directly attached, and the manufacturing process mayinclude making a cut between adjacent axial support components.

FIG. 28 is a drawing of the structure of FIG. 27 having a plurality ofcuts each between a pair of adjacent axial support components.

FIG. 29 is a side view of a tubular member according to the teachingsherein being pushed through a tortuous path.

DETAILED DESCRIPTION

The devices, methods, and apparatus according to the teachings herein,provide a tubular member having a structure that can be easily insertedinto a curved passageway and provides an at least partially containedpassage within the tubular structure for inserting a functionalcomponent into the curved passageway. The tubular member employs aplurality of axial support components that are aligned along an axis(e.g., in the length direction) of the tubular member which are shapedto allow for a rocking motion between some or all of the adjacent axialsupport components. The structure of the tubular members provides forone or more (e.g., all of the following benefits): ease of bending ofthe tubular member, resistance of kinking and/or obstruction of thepassage of the tubular member, or increased efficiency in transferringaxial forces for the insertion of the tubular member into a curvedpassageway. With such properties, a structure preferably may either beactively manipulated, or passively adapted to the shape of a tortuouspath as the structure is pushed through the path. The adjacent axialsupport components (e.g., adjacent along the length direction of thetubular member) are not directly connected at one or more positions ofcontact, so that the adjacent axial support components can rock in oneor more directions (e.g., in a forward direction and/or in a backwarddirection) for the bending of the tubular member. A steering componentmay be employed for controlling the direction of bend of an end of thetubular member. When in a tilted state, adjacent axial supportcomponents preferably maintain two or more spaced apart regions orpoints of contact, so that transfer of axial forces is improved.

A stacked arrangement of short rigid cylindrical tubes each having alength and each having the same uniform cross-section may be employed ina bendable tube. However, when adjacent cylindrical tubes are bentrelative to one another, there will only be a single point of contactbetween the two components. Such an arrangement will make it difficultto apply an axial force for translational motion in the axial direction,as this force will be focused at the single contact point.

By employing axial support components having a multiple contact pointswhen tilted, it may be easier to apply a force necessary to insert thetubular member into a passage.

Tubular Member

The tubular member has a passage (e.g., a primary passage) extendingfrom a first end (e.g., a proximal end) to a second end (e.g. a distalend). The tubular member includes a plurality of components (e.g., axialsupport components and lateral support components) that allow thetubular member to bend while maintaining a continuous passage from thefirst end to the second end. It will be appreciated that the passagethrough the tubular member has an axial direction that may becurvilinear and capable of changing to conform to the shape of a passage(e.g., a body passage) through which the tubular member is inserted. Thetubular member has an inner surface facing the passage of the tubularmember and an opposing outer surface. The components of the tubularmember may be arranged so that the axial direction of the passage isgenerally linear and the tubular member has an initial length in theaxial direction. When the passage of the tubular member is in a curvedconfiguration, the length of passage is generally maintained at aboutthe initial length.

The cross-section of the tubular member perpendicular to the axialdirection of the passage may have any shape. For example, thecross-section may have a generally circular shape, a generallyelliptical shape, a generally oval shape, a generally lens shape, agenerally arch shape, a generally egg shape, or a generally polygonalshape. Preferably, the tubular member has a cross-section having acircular shape, an elliptical shape or an oval shape. Most preferably,the tubular member has a cross-section having a circular shape.

It will be appreciated that the tubular member generally has a proximalend, a distal end, an outer surface, an inner surface, an axialdirection along a length of the tubular member, a passage extending fromthe proximal end to the distal end in the axial direction, and across-section perpendicular to the axial direction.

Axial Support Components

Each tubular member includes a plurality of axial support components.Each axial support component includes a passage extending the length ofthe axial support component. The passages of the axial supportcomponents are aligned for forming at least a portion of the passage ofthe tubular member. Each axial support component includes one or morewalls in the direction of the passage for transferring a force in theaxial direction from one axial support component to an adjacent axialsupport component. The one or more walls of the axial support componentgenerally extend around a circumference of the axial support component.However, the walls of some or all of the axial support component do notcompletely surround the passage. Instead, as discussed herein, some orall of the axial support components includes a cut-out region or otheropening formed between two adjacent axial support components, so thatthe axial support components can rock back and forth relative to eachother. As such, the axial direction (e.g., of a passage) of an axialsupport component may tilt relative to the axial direction of anadjacent axial support component. This rocking/tilting motion of theaxial support components allows them to pass through an opening that isnot straight.

The rocking or tilting motion of two adjacent axial support componentsoccurs at one or more regions or points of contact between the adjacentaxial support components. At least one of the axial support componentshas a rocking portion (e.g. a lobe region) where the outer surface ofthe axial support component is convex. One of the axial supportcomponents may have a generally flat surface in the region of contact sothat the rocking motion is defined by the rocking of the convex surfaceagainst a generally planar surface. Alternatively, both axial supportcomponents may have a convex surface in the region of contact. It willbe appreciated that in addition to one of the axial support componentshaving a generally convex shape in the rocking portion, the two axialsupport components may have a mating structure that assists in thealignment of the two components. For example, the axial supportcomponents may have mating gears, mating groove and channel. Preferably,any such mating structure does not interfere with the rocking movementbetween the two axial support components.

A pair of adjacent axial support components includes two spaced apartregions where contact is maintained as they tilt or rock against eachother. The multiple spaced apart contacts between adjacent axial supportcomponents increases the ability to translate axial forces and/or axialmotion between the adjacent axial support components (e.g., and alongthe length of the tubular member). The ability for adjacent axialsupport components to freely rock may allow for the use of generallyrigid materials, as there is no need for the material of the axialsupport component to bend. In contrast, it is desirable for the axialsupport component to be generally stiff and resist bending or otherdeformation.

Due to the rocking motion, adjacent axial support component may be ableto tilt to a higher angle than in a tubular member where the tilting isrestricted to the bending of the material. As such, the tubular memberaccording to the teachings herein may allow for bending at a low radiusand/or allow for tubular members having a large diameter (or a largercross-sectional area).

An axial support component may generally have a ring shape. The ringshape may be a closed ring (such that there is a continuous path aboutthe circumference of the axial support component. A tubular memberincluding axial support components having a closed ring shape is seenfor example in FIG. 5. The ring shape may be an open ring, having afirst circumferential end and a second circumferential end. For example,the first end and the second circumferential end may be separated in theaxial direction. An example of an open ring is a helical structure, suchas illustrated in FIGS. 21 and 22. The ring shape, may be most easilyseen when viewing an axial support component from the top, such as shownin FIGS. 18 and 20 for an open ring and FIG. 12 for a tubular memberhaving axial support components with a closed ring shape. The ring shapepreferably has a shape that increases the ease of inserting the tubularmember into a passage or other opening. For example, the ring shape maybe free of sharp corners. Most preferably the ring shape is a circularshape, an oval shape, an egg shape, an elliptical shape, or other shapehaving only curved or rounded corners.

Preferably, some or all of the axial support components include twospaced apart rocking regions which are connected by one or more lateralconnectors. The spaced apart rocking regions may be lobed regions. Therocking regions are preferably spaced apart along the circumference ofthe axial support component. For example, the rocking regions may bespaced apart by an angle of about 120° to about 240°, and mostpreferably about 180° (i.e., 180°+/−20°, +/−10°, or +/−5°) as defined bythe angle from the axis in the center of the passage of axial supportcomponent to the two rocking regions as projected onto a planeperpendicular to the axis.

It will be appreciated that a pair of spaced apart rocking regions maycooperate to tilt the axial support component relative to an adjacentaxial support component. The cooperation between the two spaced apartrocking regions may be enhanced by a lateral connector. In the case of aclosed ring, the rocking regions may be connected along opposing sides(e.g., a first lateral connector along a right side and a second lateralconnector along a left side). In the case of an open ring structure,such as a helical ring structure, a rocking region may be connected tospaced apart rocking region using a first lateral connector, andpreferably to a second spaced apart rocking region using a secondlateral connector. One or more of the lateral connectors in an axialsupport component may have a height (in the length direction of theaxial support component) that is less than the height the axial supportcomponent in the rocking region so that an opening or cut out region isformed that allows the two axial support components to approach eachother as they are tilted and rocked. A lateral connector preferably hasa sufficient thickness and height so that the spacing between the tworocking regions is generally maintained.

The rocking region (e.g., lobe region) of the axial support componentand the lateral connector of the axial support component may be formedof materials that are the same or different. Preferably, the rockingregion and the lateral connector are formed of the same material. Morepreferably, an entire ring structure of the axial support component oreven an entire axial support component is a monolithic structure, andmost preferably formed of a single material.

An axial support component may be made of a material sufficiently rigidso that axial forces can be transferred along the length of the tubularmember. The axial support component may be formed of one or more metals,one or more polymers, or one or more ceramics, one or more reinforcingfillers, or any combination thereof. Preferably, the axial supportcomponent is formed of a material including one or more polymers. Forexample, the axial support component may be formed of a polymericmaterial having a flexural modulus of about 100 MPa or more, about 250MPa or more, about 600 MPa or more, or about 1500 MPa or more, or about2000 MPa or more. Unless otherwise specified, the flexural modulus maybe measured according to ASTM D790B. Typically, polymeric materials havea flex modulus of about 8000 MPa or less, or about 4000 MPa or less.

The axial support component may have an axis of rotation (e.g., theaxial direction of a passageway extending the length of the axialsupport component). The axial support component typically is notsymmetrical about the axis of rotation.

Each axial support component has an opening at each end for forming atleast a portion of the passage of the tubular member. The alignment ofthe axial support components allows for the continuous, generallyunobstructed passage of the tubular member through the axial supportcomponents. In addition to the openings at the ends, an axial supportcomponent may have openings along the sides for the flow of a fluid intoand/or out of the passage. Such side openings may allow for theequilibration of a pressure within and outside of the passage or forremoval of a liquid through the tubular member. It may be desirable fora section of the tubular member to have side openings and for a sectionof the tubular member to be generally free of such side opening.

Two adjacent axial support components generally are configured so thatthey may tilt relative to each other. The tilting preferably is in asingle plane. The tilting of a second axial support component relativeto a first axial support component may be in one direction (e.g., aforward direction or a backward direction) or may be in two directions(e.g., both a forward direction and a backward direction). When tilted,the two adjacent axial support components remain in contact at two ormore spaced apart positions.

A first axial support component may have a first axial end and anopposing second axial end. The first axial support component may bearranged between a second axial support component and a third axialsupport component. The first axial end of the first axial supportcomponent may contact the second axial support component and the secondaxial end of the first axial support component may contact the thirdaxial support component. The second axial support component may becapable of tilting in a first angular direction (i.e., about a firsttilt axis) relative to the first axial support component and the thirdaxial support component may be capable of tilting in a second angulardirection (i.e., about a second tilt axis) relative to the first axialsupport component that is the same or different from the firstdirection. For example, the first tilt axis may be parallel to thesecond tilt axis or may be angled. By way of example, the first tiltaxis may be perpendicular to the second tilt axis so that the secondaxial support component tilts forward and/or backward relative to thefirst axial support component and the third axial support componenttilts left and/or right relative to the first axial support component.As such, the tubular member may tilt along multiple planes so that itcan readily conform to the shape of a passage that is non-planar.

The cross sectional shape of the axial support component is not uniformalong the length of the axial support unit (i.e., in the axialdirection).

The adjacent support components may tilt about a tilt axis defined by aline connecting two spaced apart contact points. An axial supportcomponent may have a region proximate to a second axial supportcomponent where the two axial support components tilt about a tilt axis.

The axial support components may be arranged in a generally helicalshape. For example, a single turn of the helical shape may define anaxial support component having one or more (e.g., two or three or more)and preferably two contact regions with an adjacent axial supportcomponent. The tilting of the adjacent axial support components may beaccomplished by the cooperative rocking at two spaced apart contactregions. As the contact regions may be offset along the lengthdirection, it will be appreciated that the tilt axis may be angledrelative to the planes normal to the length direction of each of theaxial support components. At each contact region, at least one of theaxial support components has a generally convex outer surface forrocking against a surface of the adjacent axial support component. Twospaced apart rocking regions may be connected by a lateral connector.For example, two spaced apart rocking regions of a first axial supportcomponent may be connected by a first lateral connector and a rockingregion of the first axial support component may be connected to arocking region of an adjacent axial support component by a secondlateral connector.

The tubular member may have a large number of axial support componentsso that the tubular member can bend along a tortuous path. The number ofaxial support components in the tubular member preferably is about 10 ormore, more preferably about 20 or more, even more preferably about 40 ormore and most preferably about 60 or more.

The tubular members may be assembled by stacking discrete axial supportcomponents. It may be beneficial to reduce the number of different partsto be assembled. As such, two or more of the axial support componentsmay have the same shape or be identical. Most, substantially all of, orall of the axial support components may be selected from a small groupof 4 or less different shaped components (or even 2 or less differentshape components. For example, 20% or more, 50% or more, or 80% or moreof the axial support components may generally have the same shape or beidentical.

Preferably, the stack of axial support components includes one or anycombination of the following features: (i) two adjacent axial supportcomponents that generally have the same shape or are identical; (ii) twoaxial support components, separated by a single axial support component,that are generally have the same shape or are identical; or two axialsupport components, separated by exactly three axial support components,that generally have the same shape or are identical.

Although two axial support components may have the same shape or beidentical, it will be appreciated that the two components may be alignedin various configurations. For example, the two axial support componentsmay be rotated (e.g., at about 45 degrees, 90 degrees, 135 degrees, or180 degrees) about the axial direction of the tubular member. As anotherexample, the two axial support components may be inverted relative toone another. As another example, they two axial support components maybe both rotated and inverted.

A pair of adjacent axial support components may be capable of tilting byan angle of (i.e., may have a maximum tilt angle of) about 3° or more,about 7° or more, about 15° or more, about 28° or more, about 36° ormore or about 44° or more. The maximum tilt angle may be about 70° orless, about 55° or less, or about 45° or less. The maximum tilt anglebetween a first and an adjacent second axial support component may bethe maximum acute angle between the axial direction of the passages inthe two adjacent axial support components.

Axial support components may be arranged in a spiral configuration. Forexample, the axial support component may be in the form of an open ring.One or more ends of an open ring may be connected with an end of anotheraxial support component. For example, all of the axial supportcomponents may be connected to form a long spiral. The axial supportcomponent may have a periodicity, L_(p). Along the circumference of thespiral, there may be contact regions where the axial support componenthas a length (i.e., in the axial direction), L_(c) about equal to theperiodicity, L_(p), so that adjacent spirals can contact in theseregions. Between the contact regions, there are regions where the lengthof the axial support component is reduced, so that the adjacent axialsupport components can tilt (i.e., rock). The regions of reduced lengthmay be referred to as cut-out regions. Every ring, or every turn of thespiral, preferably has 2 or more, 3 or more, or 4 or more contactregions. For example, if there are 2 contact regions (e.g., at about 90°and at about 270° angles about the spiral) per turn of the spiral, thetubular member may be able to tilt back and forth (e.g., in thedirection of about 0° and about 180° angle about the spiral). As anotherexample, if there are 4 contact regions per turn of the spiral, thetubular member may be able to tilt back and forth and also tilt left andright. It will be appreciated that intermediate tilt directions can beachieved by tilting in multiple directions. As such, it may be possibleto use the tubular member to navigate a passage that is curved ortortuous in three dimensions.

The axial support components may be formed of a single material or fromtwo or more materials (e.g., to form a composite structure or areinforced structure). By way of example, the axial support componentmay include one or more metal materials, one or more polymer materials,or one or more ceramic materials. The axial support component mayinclude one or more filler reinforcements, such as a particulatereinforcement or a fiber reinforcement. The selection of the materialfor the axial support components may be the result of manufacturing orcost considerations. For example, in a polymer fabrication process(e.g., a molding, an extrusion or a blow molding process), the materialmay include a polymer composition selected for ease of use in thefabrication process. As another example, in a 3D manufacturing process,the material may include one or more material employed in the art of 3Dmanufacturing. The material for the axial support components should beselected so that an axial force for the insertion of the tubular memberinto a passageway can be partially or entirely translated from axialsupport component to axial support component along the length of thetubular member.

Lateral Support Components

The tubular member includes one or more lateral support components. Alateral support component preferably functions to reduce, minimize oreliminate lateral movement between adjacent axial support componentsand/or to reduce, minimize, or eliminate axial separation betweenadjacent axial support components. Preferred lateral support componentsare in contact with or connected with two adjacent axial supportcomponents. For example, a lateral support component may reduce oreliminate lateral movement of adjacent axial support components relativeto each other (except for the rocking or tilting motion as describedherein). Preferably, there is a lateral support component for eachadjacent pair of axial support components.

Preferably, the lateral support components allow for the adjacent axialsupport components to rock relative to each other. As such, the lateralsupport components should be formed of a material or include one or morefeatures that allow the axial direction of the passage through a firstaxial support component to be tilted relative to the axial direction ofthe passage through an adjacent axial support component. For example,the lateral support component may have a lower wall thickness, mayinclude hinge features (e.g., one or more crests or valleys and/or oneor more ridges or roots, such as in a bellows), may have an axial lengththat is relatively low (e.g., the ratio of the axial length of a lateralsupport component to the axial length of an axial support component maybe about 0.7 or less, about 0.5 or less, about 0.35 or less, or about0.20 or less, may be formed of a material having a lower flexuralmodulus relative to the material of the axial support component, or anycombination thereof.

Although, the axial support components and the lateral supportcomponents may be made of the same materials or may be made of differentmaterials, in one approach the lateral support component preferably ismade of a material that is different from the axial support component oris shaped to allow for the rocking motion of adjacent axial supportcomponents. As one example, the lateral support component may be asupport layer (such as a cylindrical layer or other tubular layer) overthe outside surface of the axial support components and/or a supportlayer within the inside surface of the axial support components. Such asupport layer may be sufficiently flexible and/or sufficiently thin soit can bend (e.g., with the rocking movement of the axial supportcomponents) without kinking or obstructing the passage through thetubular member. A support layer preferably extends at least the lengthof the axial support components, and may even extend about the entirelength of the tubular member. A support layer preferably is provided asa tubular shaped sheet, a fabric layer, or a combination thereof. Thesupport layer preferably contacts the axial support components or isseparated by the axial support components by a nominal gap distance(e.g., a gap distance of about 0.5 mm or less, about 0.2 mm or less,about 0.1 mm or less, or about 0.03 mm or less). The support layer maybe attached to one or more (or even all of the axial supportcomponents). However, if a support layer is attached to a plurality ofaxial support components, it preferably is attached at a location and/orin a manner that does not prohibit the rocking motion between adjacentaxial support components. For example, the support layer may be attachednear a lateral connector region. Preferred support layers are formed ofa polymeric material. The polymeric material may be a monolithicmaterial. The polymeric material may be a woven or nonwoven fabric.Preferred polymeric materials include one or more amorphous polymers(e.g., having a glass transition temperature above a use temperature, sothat the polymer is substantially below its glass transition temperatureat one or more use temperatures), one or more semi-crystalline polymers(e.g., having a final melting temperature above a use temperature, sothat the semi-crystalline polymer has at least some crystallinestructure at the use temperature), or a combination thereof. Preferredsemi-crystalline polymers have a final melting temperature. of about 40°C. or more, about 60° C. or more, or about 80° C. or more, as measuredby differential scanning calorimetry. The semi-crystalline polymer mayhave a final melting temperature of about 360° C. or less, about 200° C.or less, or about 150° C. or less, as measured by differential scanningcalorimetry. The semi-crystalline polymer preferably has a crystallinityof about 1 percent or more, more preferably about 4 percent or more, andmost preferably about 9 percent or more, as measured by differentialscanning calorimetry. The semi-crystalline polymer preferably has acrystallinity of about 50 percent or less, more preferably about 40percent or less, even more preferably about 30 percent or less, and mostpreferably about 25 percent or less. The lateral support component mayinclude or be made from a fabric. Preferred fabrics are stretchable.Stretchable fabrics may be made from a material and or woven so that thefabric can be stretched. Preferably, the stretchable fabric has anelongation in one or more directions of about 5% or more, about 10% ormore, about 20% or more, about 30% or more, or about 50% or more (asmeasured according to ASTM D3107-07 after 30 minutes at a tension of 3pounds). The stretch fabric preferably includes, consists substantiallyof (e.g., includes 80% or more, 90% or more, or 95% or more), orconsists entirely of one or more elastic yarns. For example, the stretchfabric may recover some (about 50% or more, about 75% or more, about 90%or more, or about 95% or more) or all of its stretched portion uponremoval of the tension. The lateral support component may be formed of amaterial having a lower hardness (e.g., as measured according to ASTM D2240 in units of Shore A durometer or Shore D durometer) than a materialemployed in the axial support component. Preferably, the difference inthe Shore A durometer of the material of the axial support componentless the Shore A durometer of the material of the lateral supportcomponent is about 5 or more, about 10 or more, about 15 or more, orabout 25 or more (in Shore A units).

As another example, a lateral support component may be connected to eachof two adjacent axial support components and include one or more hingesthat allows for the rocking motion between the axial support components.Such a lateral support component may even be formed of the same materialas the axial support components. For example, the lateral supportcomponent may have a bellows shape (e.g., having a cross-section withone or more ridges and one or more valleys). Such a lateral supportcomponent may span the space between lateral connectors of the adjacentaxial support components, such as described herein. For example, as thelateral connectors rock towards each other, the bellows may becomecompressed, so that the distance between the valleys become decreased.When the lateral connectors rock away from each other, the bellows maybecome expanded, so that the distance between the valleys is increased.

A lateral support component may seal off some or all of the openings inthe axial support components. For example, the tubular member may onlyhave openings at the ends of the passage. It will be appreciated thatthe lateral support component may have openings which allow for the flowof a fluid into the passage through a side of the tubular member.

A surface of the tubular member (e.g., an outer surface or an innersurface of the tubular member) may be hydrophilic and/or lubricious.Such a characteristic may be obtained by the selection of material for acomponent of the tubular member (e.g., an axial support component or alateral support component), by treating a surface of the tubular member,or by an additional layer or component.

The tubular member may include one or more control components forsteering a leading end of the tubular member. For example, the tubularmember may include one or more cables connected to the leading end to besteered. By applying a tension to a cable, the direction of tilt of aleading end may be controlled. The tubular member may include one ormore eyelets or other spaced apart along the length of the tubularmember for managing the position of the cables in the passage of thetubular member. For example, the tubular member may include eyeletsprotruding from the axial support components (e.g., in the region of thelateral connectors) into the passage of the tubular member. Preferablythe tubular member includes two or more spaced apart control cables.

The tubular member may include one or more covers, such as a cover overthe axial support components. The cover may provide a protection to theaxial support component or a protection a passageway from damage by theaxial support component. The cover, if employed, may provide afunctional feature for an intended application.

The tubular member may include a lumen, such as a central lumen. Ifemployed the lumen may be porous or non-porous.

The tubular member according to the teachings herein is preferablyemployed in an application requiring the insertion of the tubular memberinto a curved passage and/or requiring the steering of the leading endof the tubular member.

The device may include a functional component in the passage of thetubular member or may be adapted for receiving a functional component inthe passage. It will be appreciated that the device may be supplied as akit including both the functional component and the device including thetubular member. The functional component may be a component for one orany combination of the following: delivering an item for a medicalprocedure, viewing a medical procedure, removing an item from a medicalprocedure, positioning a medical component within or adjacent to anorgan or body part, attaching a medical component to an organ or bodypart, making a surgical incision, and repairing an organ or body part.

The tubular member according to the teachings herein may be employed ina medical application. For example, the tubular member may be employedfor a stent, an access catheter, an access cannula or an access sheath.The tubular member may be employed as an utereral access sheath, such asfor access to a bladder or a kidney. The tubular member may be employedfor the removal of a stone or stone fragment, such as the hydraulicremoval of a stone or stone fragment. The tubular member may be employedduring lithotripsy, such as an intrarenal lithotripsy.

Process of Manufacture

The components and or tubular members according to the teachings hereinmay be manufactured by any known process. For example, a component maybe manufactured using a process including molding (e.g., injectionmolding or compression molding), casting, extrusion, blow molding,co-injection molding, insert molding, or any combination thereof,layered printing (i.e., 3D printing), machining (such as cutting,milling, drilling), or any combination thereof.

Two or more axial support components may be manufactured as an attachedmulti-component structure or may be manufactured as individual units.The process may include a step of stacking two or more individual unitsor stacking two or more multi-component structures. It will beappreciated that all of the axial support components may be manufacturedas a single multi-component structure (e.g., in a stacked arrangement)so that there is no need for stacking of the axial support components.The manufacturing process may include one or both of the followingsteps: slicing or otherwise separating two or more axial supportcomponents (e.g., in a contact region and/or rocking region), cuttingout one or more openings (e.g., to form a cut-out region, such asbetween two lateral connectors). Such step(s) may be of particular usewhen the axial support components are manufactured as a singlemulti-component structure.

A molding process may be employed for manufacturing an axial supportcomponent. A lateral support component may optionally also be molded(e.g., from the same material, or preferably from a different material,such as a material having a lower flexural modulus). A preferred moldingis an injection molding process, such as a polymer injection moldingprocess. If the process includes molding the axial support component(s)and the lateral support component(s) from different material, theprocess may employ a co-injection molding process or an overmoldingprocess, for sequentially forming the two components.

The axial support components may be formed by an extrusion process, suchas a polymer extrusion process. For example, a polymeric tube may beextruded and then processed so that the cut-out regions are formed, therocking regions are formed, and at least the contact regions areseparated so that the adjacent axial support components can rock in oneor more directions. It will be appreciated that the extrusion processmay include extruding one or more layers. For example, a functionalsurface layer may be co-extruded with a structural layer.

The axial support components may be formed using a blow molding process,such as a polymer blow molding process. Such a process may beparticularly useful for simultaneously forming a structure for multipleaxial support component and for multiple lateral support components. Forexample, the blow molding process may produce sections having ridges andvalleys (e.g., for the lateral support components) with other sectionsthat suitable for forming the axial support components.

The axial support components may be formed by a layered printing processor other 3D printing process. Such a process may employ a polymericmaterial, a ceramic material, a particulate material, a binder material,a metallic material, or any combination thereof. The layered or other 3Dprinting process may be employed for producing individual axial supportcomponents or for producing a stacked arrangement of a plurality ofaxial support components. It will be appreciated that a layered or other3D printing process may also be employed for simultaneously printing alateral support component (using the same or different material).

EXAMPLES

A tubular member 2 may be capable of being arranged in a generallystraight configuration, such as illustrated by FIG. 1. The tubularmember 2 has an axial direction 6, which is generally uniform when thetubular member is in a straight configuration. The tubular member has anouter surface 4. The outer surface 4 may cover the entire length andcircumference of the tubular member, or the tubular member may haveopenings, cut-outs, or other passages along the length of the tubularmember. The tubular member has a first end 10 and an opposing second end11, and a passage extending the length of the tubular member from thefirst end to the second end. The tubular member 2 may also be arrangedin a curved configuration 8, so that at least a portion of its length isgenerally curved, such as illustrated in FIG. 2. With reference to FIG.2, the axial direction 6, 6′, 6″ may vary along the length of thetubular member 2. For example, the tubular member may include one ormore regions having a generally uniform or constant axial direction 6,and/or one or more regions having an axial direction that varies alongthe length of the tubular member.

The tubular member 2 preferably is steerable so that it can be insertedinto a curved or even a tortuous passage, such as illustrated in FIG. 3.As the tubular member 2 is inserted into the curved or tortuous passage,a leading end of the tubular member may be steered along the boundaryand/or walls 16 of the passage.

FIG. 4 is a side view showing features of a device including a tubularmember 2 according to the teachings herein, and having a functionalcomponent 22 extending through the passage 12 of the tubular member 2.The tubular member includes a plurality of axial support components 18,18′. Adjacent tubular members may be different, or may havesubstantially identical shapes, such as illustrated in FIG. 4. Theadjacent axial support components (e.g., 18, 18′) contact at multiplespaced apart contact points (e.g., two contact points). Axial forcesrequired for inserting a tubular member into a passage may betransferred between adjacent axial support members through the contactpoints. The tubular member 2 also includes one or more lateral supportcomponents 20. The lateral support components may provide lateralstability to the tubular member 2, so that adjacent axial supportcomponents generally remain aligned for providing a sufficient andcontinuous passage 12 for the functional components 22 to pass through.The one or more lateral support components may include or consistessentially of one or more support sheaths, such as a tubular sheathinserted inside the passage formed by the axial support componentsand/or a tubular sheath positioned outside the axial support components.Such a support sheath preferably is capable of flexing without kinking,so that axial support components can tilt relative to each other withoutobstructing or blocking the passage of the tubular component. A supportsheath preferably contacts a surface of the axial support components oris within a narrow gap (e.g., about 1 mm or less, about 0.2 mm or less,about 0.1 mm or less, or about 0.05 mm or less) of the axial supportcomponents for defining the lateral alignment of the axial supportcomponents.

FIG. 5 is a perspective view showing a portion of the tubular member ofFIG. 4. With reference to FIG. 5, the axial support components 18, 18′have a structure that allow adjacent axial support components to tilt inone or more directions. The axial support components may have a firstedge surface (e.g., a top edge surface) 26 and an opposing second edgesurface (e.g., a bottom edge surface) 28. The top edge surface of oneaxial support component 18 may face the bottom edge surface 28 of anadjacent axial support component 18′. Adjacent axial support components(e.g., 18 and 18′, or 18 and 18″) may contact at two spaced apartcontact regions or contact points 24. One or both of the adjacent axialsupport components may have a lobe region(s) 30 that includes thecontact region or contact points 24. For example, as illustrated in FIG.5, both adjacent axial support components may have lobe regions thatmeet at two spaced apart contact points 24 (only one of the two contactpoints between 18 and 18′ is visible in FIG. 5). The axial supportcomponent may include regions 25 that do not contact an adjacent axialsupport component. The tubular member may include cut-out regions 32between adjacent axial support components. It will be appreciated that acut-out region 32 may be formed by cutting out material or may be astructure defined by the shape and arrangement of adjacent axial supportcomponents. The tubular member may have one or more rigid regions 33,where the tubular member generally does not bend. Preferably any rigidregions are positioned at one of the ends 10, 11, and most preferably atthe second end 11 (e.g., an end that will not be inserted into a curvedpassage). The device may include one or more control components (e.g.,guide wires) 34 for steering or otherwise controlling a tilt of thetubular component. The tubular member may have a cover layer or supportsheath 36 (shown as a transparent layer). The features shown in FIG. 5are further illustrated in FIG. 6 (front view) and FIG. 7 (side view).

With reference to FIG. 6, the adjacent axial support components 18, 18′,18″ may tilt about a tilt axis 40. When two adjacent axial supportcomponents tilt in the forward direction about the tilt axis 40, theirfacing edge surfaces 26, 28 in the front cut-out region 32 may movetogether in a contracting direction 41 with the cut-out region 32decreasing in size. As shown in FIG. 7, a first portion 42 of theadjacent axial support components move together (e.g., in a contractingdirection 41) and a second portion 44 of the adjacent axial supportcomponents move apart (e.g., in an expanding direction 43). During thetilt of the adjacent axial support components, two points or regions ofcontact 24 are maintained. It will be appreciated that the axialcomponents in FIGS. 5, 6, and 7 can also tilt in a reverse or backwarddirection due to the mirror symmetry (about a plane defined by the axialdirection and the tilt axis) of each axial support components. Thetubular member may have an end region 38 that is generally rigid. Forexample, the end region 38 may have a structure that reduces, minimizes,or prevents bending. As illustrated in FIG. 6 and FIG. 7, the end region38 may be a generally solid tubular region (e.g., without cut-outs,slits, or other openings). The end region 38 may include one or morestructures for attaching the tubular member 2 to other components. Forexample, the end region 38 may be threaded, such as shown in FIG. 6 andFIG. 7. FIG. 8 is an enlarged view of a region of FIG. 6.

Some or all of the axial support components may include an eyelet 66 orother component for supporting the control component 34 (not shown),such as illustrated in FIG. 9. Preferably, tubular member includes asufficient number of eyelets or other components for positioning one ormore (preferably two or more) control components in the passage of thetubular member. For example, one or more (preferably each) of the axialsupport components may have a pair of spaced apart eyelets forpositioning two spaced apart guide wires. With reference to FIG. 10, thecontrol components 34 may be threaded through the eyelets 66. Thetubular member may have one or more tethers 68, such as illustrated inFIG. 11.

Preferably the tubular member 2 includes a first set of eyelets 66 and asecond set of eyelets 66′ which are spaced apart (e.g., by about 180°),such as illustrated in FIG. 12. The eyelets may include an opening for67 for threading a control component through. It will be appreciatedthat the tubular member may include additional sets of eyelets forcontrolling a tilt of the end of the tubular member in more than twodirections. By way of example, the tubular member may include three ormore sets of eyelets (e.g., three sets of eyelets spaced apart by about120°, or four sets of eyelets spaced apart by 90°). Two sets of eyeletsmay allow for the steering of an end of the tubular member in a singledirection (e.g., in a forward and backward direction). Two sets ofeyelets arranged at a 90° angle may allow for the independent steeringof the tubular member in two orthogonal directions (e.g., in a front orback direction and in a right or left direction). It will be appreciatedthat additional steering of the tubular member may be facilitated byrotating the tubular member.

As discussed herein, when adjacent axial support components are tilted,they preferably maintain two spaced apart contact points or contactregions. However, such multiple contacts is not typically achieved ifthe axial support components are regular cylindrical tubes 70, such asillustrated in FIG. 13. These axial support components 70 may bearranged in a stacked arrangement, such as illustrated in FIG. 14. Asthe cylinders have the same dimensions and mate together, completecontact between the facing surfaces is achieved when the tubular memberis in a linear arrangement. However, when the tubular member is bent,such as illustrated in FIG. 15, there is only a single point or regionof contact between adjacent axial support components 70. When in thisbent or tilted arrangement with a single point of contact, it may bedifficult to effectively transfer axial forces along a series of stackedaxial support components.

The axial support components may be arranged in a helical structure,such as illustrated in FIG. 16A, FIG. 16B, and FIG. 16C, showing astructure that includes a plurality of axial support components havingthe open ring structure illustrated in FIGS. 20, 21, and 22. Preferably,an axial support component is represented by a single turn of the helix.Each turn of the helix preferably includes two or more lobe regions(e.g., where the axial support component can rock or tilt against anadjacent axial support component). Although an axial support componentmay include three or more spaced apart lobe regions, it preferably hastwo lobe regions for contacting one of the adjacent axial supportcomponents at two contact regions (for example spaced apart at an angleof about 180°). A first lobe region 30 may be connected to another loberegion 30 of the axial support component via a lateral connector 76. Thefirst lobe region 30 may also be connected to a lobe region of anadjacent axial support component by another lateral connector 76, suchas illustrated in FIG. 16B. Although the axial support components mayhave lateral connectors 76, the adjacent axial support components arenot directly connected at the contact points or contact regions 24. Itwill be appreciated that when the axial support components tilt, theymay tilt about different tilt axis when tilting in a generally forwarddirection compared to when tilting in a generally rearward direction. Asillustrated in FIG. 16B, the tilt axis for tilting in a forwarddirection 40 may be angled relative to the tilt axis for tilting in agenerally rearward direction 40′. With reference to FIG. 16C and FIG.17B, an axial support component may include a lobe region 30 for rockingor tilting against a lower axial support component and/or a lobe region30 for rocking or tilting against a high axial support component. Theaxial support components provide a generally unobstructed passage 12 atleast partially surrounded by the walls of the axial support components,such as illustrated in FIG. 18. In the case of the helical arrangement,the rocking or tilting is provided by the cooperative tilting at twocontact points or contact regions that are also spaced apart in thelength direction. For example, the two contact points or contact regions24 may be spaced apart by a fraction turn (e.g., a half turn) of thehelix, such as shown in FIG. 16B.

Two axial support components may have facing surfaces that include afirst portion that mates with (e.g, the first portion may be coplanar)and a second portion that is separated, such as illustrated in FIG. 23A.The facing surfaces of the two axial support components may have acontact area that is generally large (e.g, about 2 percent or more,about 5 percent or more, about 10 percent or more, or about 15 percentor more, based on the total area of the facing surface) when the twoaxial support components are in a “rest state”, such as a generallyaligned state (e.g., when their axial directions are aligned). In suchan aligned state, the ratio of the contact area to the total area of thefacing surface is typically about 90 percent or less, about 70 percentor less, about 60 percent or less, or about 55 percent or less. When thetwo axial support components are rocked (i.e., tilted) so that theiraxial directions are angled with respect to one another, the contactbetween the axial support component decreases and is typically about 5percent or less, about 3 percent or less, about 2 percent or less, orabout 1 percent or less of the total area of the facing surface. In sucha tilted arrangement, the contact may be limited to two regions orpoints of contact that are spaced apart. The two regions or points ofcontact preferably are spaced apart by an angle (i.e. a spread angle) ofabout 60 degrees or more, more preferably about 90 degrees or more, evenmore preferably about 120 degrees or more, and most preferably about 150degrees or more, as measured from the axis of the passage of the axialsupport component. It will be appreciated that the spread angle betweenthe spaced apart contact regions may change with the degree of tilt. Forexample, in some applications it may be desired for the spread anglebetween the spaced apart contact regions may increase and then decreaseas the tilt between the two axial support components increases. In otherapplications, the axial support components may be configured so that thespread angle between the spaced apart contact regions continuouslydecrease as the tilt between the two axial support components increases.

It will be appreciated that rocker portion (e.g., a lobe region) of anaxial support component may rock against a generally flat portion of anadjacent axial support component (such as shown in FIG. 23A) or againsta generally curved portion, such as a lobe region, of an adjacentsupport component (such as shown in FIG. 24A).

REFERENCE NUMBERS

-   -   2 Tubular member    -   4 Outer surface of the tubular member    -   6 Axial direction/axis of the tubular member    -   8 Curved configuration of tubular member    -   10 First end    -   11 Second end    -   12 Passage extending the length of the tubular member    -   14 Tubular member in a tortuous passage    -   16 Boundary and/or wall of the tortuous passage    -   18, 18′, 18″, 18′″ Axial support component    -   19 Passage extending the length of an axial support component    -   20 Lateral support component    -   22 Functional component    -   24 Contact regions (e.g., contact points) of two adjacent axial        support components    -   25 Regions of axial support component (e.g., top or bottom edge        surface) that do not contact another axial support component.    -   26 Top surface (e.g., top edge surface) of the axial support        component    -   27 Inside surface of axial support component    -   28 Bottom surface (e.g., bottom edge surface) of the axial        support component    -   29 Outside surface of axial support component    -   30 Rocking region or rocker portion (e.g., lobe region) of axial        support component    -   32 Cut-out region of axial support component    -   34 Control components (e.g., for steering the tubular member,        such as guide wire or guide line)    -   36 Cover layer    -   38 End region    -   40 Tilt axis    -   41 Direction of movement between two axial adjacent support        components (e.g., on a front or rear)    -   42 Portions of adjacent axial support regions moving together        (e.g. cut-out region decreasing in size)    -   43 Direction of movement between two axial support components        (e.g., on the opposite of the front or rear of 41)    -   44 Portions of adjacent axial support regions moving apart        (e.g., cut-out region increasing in size)    -   46 Axial support components arranged for tilting in a first        direction    -   47 Axial support components arranged for tilting in a second        direction    -   48 Axial support components arranged for tilting in a third        direction    -   49 Axial support components arranged for tilting in a fourth        direction    -   50 Curved region of an edge surface (e.g., top edge or bottom        edge)    -   52 Flat surface region (e.g., horizontal) of an edge surface        (e.g., top edge or bottom edge)    -   54 Axial support components in a stacked arrangement    -   56 Tubular member including corrugated region    -   58 Corrugated region having flutes or other structure having        alternate ridges and grooves.    -   60 Space or cut between adjacent axial support components    -   62 Tubular member precursor (e.g., attached axial support        components)    -   64 Tubular member with axial support components unattached from        adjacent axial support components.    -   66 Eyelet or other component for supporting the control        component    -   67 Opening for receiving a control component    -   68 Tether    -   70 Cylinders having uniform cross-section (along the length)    -   72 Single point of contact    -   74 Helical shaped tubular member    -   76 Lateral connectors    -   78 Angular spacing between two lobe regions (i.e., angle between        80 and 81)    -   80 Direction between axis of the passage and a first lobe region    -   81 Direction between axis of the passage and a second lobe        region    -   82 Direction between axis of the passage and a lateral connector    -   84 Ridge    -   86 Valley

What is claimed is:
 1. A medical device comprising: a tubular memberhaving a proximal end, a distal end, an outer surface, an inner surface,a longitudinal direction along a length of the tubular member, a passageextending from the proximal end to the distal end extending along thelongitudinal direction, and a cross-section perpendicular to thelongitudinal direction; wherein the tubular member includes i) aplurality of discrete axial support components in a stacked arrangementincluding at least a first axial support component and a second adjacentaxial support component located above the first axial support componentin the distal direction, wherein each axial support component has a topedge surface facing the proximal end and a bottom edge surface facingthe distal end, wherein a first portion of the top edge surface of thefirst axial support component contacts a first portion of the bottomedge surface of the second axial support component (e.g., so that anaxial force is translated between the adjacent axial supportcomponents), and a second portion of the top edge surface of the firstaxial support component is spaced apart from the bottom edge surface ofthe second axial support component (e.g., so that the axial directioncan bend between adjacent axial support components), wherein the firstand second portions of the top edge surface are at different locationsalong the circumference of the first axial component; and ii) one ormore lateral support components in contact with the axial supportcomponents for reducing lateral movement of adjacent axial supportcomponents relative to each other.
 2. The device of claim 1, wherein thefirst axial support component and the second axial support componenthave the same shape.
 3. The device of claim 1, wherein the one or morelateral support components includes a central lumen having a passagetherethrough for defining at least a portion of the inner surface of thetubular member.
 4. The device of claim 1, wherein the device includesabout 10 or more stacked axial support components.
 5. The device ofclaim 4, wherein the axial support components and the lateral supportcomponents are connected.
 6. The device of claim 5, wherein the axialsupport components and the lateral support components are formed of thesame material.
 7. The device of claim 4, wherein the axial supportcomponents and the lateral support components are formed of differentmaterials.
 8. The device of claim 7, wherein the axial support componentis formed from a first material and the lateral support components isformed from a second material having a Shore A durometer less than aShore A durometer of the first material.
 9. The device of claim 7,wherein the lateral support components are formed of a stretchablefabric.
 10. The device of claim 4, wherein the lateral supportcomponents have a wall thickness that is less than a wall thickness ofthe axial support components.
 11. The device of claim 4, wherein theadjacent axial support components are not directly attached at a pointof contact between the opposing edge surfaces.
 12. The device of claim11, wherein the first axial support component rocks back and forth in afirst direction relative to the second axial support component.
 13. Thedevice of claim 1, wherein the first axial support component bends onlyin a first direction relative to the second axial support component. 14.The device of claim 4, wherein the axial support component includesstructural features for stiffening the components.
 15. The device ofclaim 4, wherein the lateral support components include a bellowsstructure.
 16. The device of claim 4, wherein the tubular member has aporous wall.
 17. The device of claim 4, wherein the outer surface of thetubular member is coated with a hydrophilic coating.
 18. The deviceclaim 1, wherein the device includes one or more control componentsextending the length of the tubular member for controlling a directionof bend of the proximal end of the tubular member.
 19. The device ofclaim 18, wherein the control components includes a first cable and asecond cable and the axial support components includes eyelet openingsin the passageway of the tubular member for threading the cables,wherein the first and second cables bend the tubular member in opposingdirections.
 20. The device of claim 19, wherein the device includes awater impermeable cover over a length of the tubular member.